feat(e12-s4/s5): homebrew tap + scoop manifest distribution

[imneov]

Summary

• Add GoReleaser Homebrew formula publishing to a2d2-dev/homebrew-tap using TAP_GITHUB_TOKEN.
• Add Windows release artifacts and Scoop manifest publishing to the same repository as the Scoop bucket.
• Document Homebrew/Scoop install commands from the next tagged release onward.
• Extend the v1.0.0 release runbook with tap/manifest verification, install/upgrade smoke tests, and rollback guidance.

External resources

• Created public repo: a2d2-dev/homebrew-tap
• Updated repo secret: TAP_GITHUB_TOKEN on a2d2-dev/claudecm
• No separate Scoop bucket repo was created; Scoop reuses a2d2-dev/homebrew-tap.

Security note

TAP_GITHUB_TOKEN currently holds a broad OAuth token; recommend replacing with a fine-grained PAT scoped to the tap/bucket repos.

Verification

• goreleaser check: passed with GoReleaser v2.11.1. It emits the current soft warning that brews is being phased out, but validates the config. The release workflow is pinned to v2.11.1 so CI uses the same behavior.
• go build ./...: passed.
• git status: clean before push, branch ahead only; after push branch tracks origin/feat/e12-s45-distribution.
• gh repo view a2d2-dev/homebrew-tap: confirmed public repo exists.
• gh secret list --repo a2d2-dev/claudecm: confirmed TAP_GITHUB_TOKEN is set.